Which of the following ratios is NOT equivalent to start fraction 4 over 8 end fraction ? A. The fraction one half or one over two is shown.
B. nine-eighteenths
C. start fraction 12 over 32 end fraction
D. start fraction 18 over 36 end fraction

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐